Multiple burner furnace



Dec. 26, 1939. c. E. SMALL MULTIPLE BURNER FURNACE Filed May 2, 1938 2 Sheets-Sheet 1 5 Man C/yde E. Sma/l INVENTOR ATTO MULTIPLE BURNER FURNACE Filed May 2, 1938 V 2 Sheets-Sheet 2 BY I Patented Dec. 26, 1939 MULTIPLE BURNER FURNACE Clyde lE. Small, Harrison. Ohio. assignor to The Campbell Hausfeld Company,

a corporation of Ohio Harrison, Ohio,

Application May 2, 1938, Serial No. 205,511

5 Claims.

The present invention relates to a multiple burner furnace such as may be used in the melt ing of non-ferrous metals and other substances not ordinarily subjected to cupola smelting.

An object of the invention is to provide a furnace of the character referred to, which is highly efficient, long lived, and practically noiseless in its operation, compared with known furnaces of a kindred type.

Another object of the invention isto provide a furnace of the kind referred to, which has the advantages of low fuel consumption and a short operatin period, with a resultant saving of time, labor and operating cost.

A further object of the invention is to enhance the quality and reduce losses of the metal or other material treated within the furnace, by reason of an even distribution of heat about the crucible and a reduction in the melting period.

Another object is to so design and arrange the constituents of the furnace as to materially increase the life of the crucible and the lining-0f the furnace, all of which makes for efiiciency of operation and low maintenance cost.

The foregoing and other objects are attained by the means described herein and disclosed in the accompanying drawings, in which:

ig. l is a side elevational view of the furnace, showing approximately half thereof in cross-section.

Fig. 2 is a top plan view of the furnace, part thereof being in cross-section taken upon line 22 of Fig. 1.

Fig. 3 is anenlarged side elevational view of a fuel distributor of the invention.

Fig. 4 is a top plan view of the fuel distributor illustrated in Fig. 3.

With reference to the accompanying drawings, the character 5 indicates the furnace drum, which may be of sheet metal formed into cylindrical shape, and provided with a bottom plate 6.. The drum may be suitably mounted for tilting movement, for example by means of trunnions l fixed to the drum and having their free ends supported in suitable journals or bearings 8 furnished by the supporting frame parts 9. Tofacilitate the tilting of the. drum about the journals 8, there may be provided a suitable hand wheel or other actuator l0, working through a reduction gear, the casing of which is indicated generally at E2.

The drum preferably is lined with suitable refractory or insulatingmaterial, which may be applied in the form of slabs or sections i3 properly arrangeclto protect the drum from the heat of the furnace. A stool orblock it may be provided within the combustion chamber formed by the lining, for supporting the crucible at a proper elevation within the furnace. The drum and lining may be cut away. as at it to permit thespout ll .of the crucible to project therethrough, so that the molten metal may be poured upon tilting of the furnace as previously explained. The combustion chamber may ybe, substantially closed by means of a suitablecover H3 of tile or other acceptable material, and the cover may be, furnished with an aperture it for the exhaust of the gases of combustion. Any suitable-means, not shown, may be provided for lifting the cover and replacing it upon the furnace, if desired. 7

As clearly indicated in Fig. 2, a fuel supply pipe. 20 is brought to the furnace in axial alignment with one of the trunnions and provided with a swivel coupling 2! so that the fuel. supply piping between the pipe 215 and the flame nozzles may move with the furnace when tilted, without rotating or twisting the pipe 23. For this purpose, it has been found convenient to employ a pipe-Y -22, one branch o-flwhich connects with the adjacent trunnion i and the other of which, indicated at. 23, connects to a short length of pipe 24 having elbow coupling connections as indicated by the characters 25, 26, and.2|. The elbow 27 connects with a riser 28 that supplies fuel to the fuel distributorwhich is about to be described.

' The fuel distributor comprisesa manifold 29 and a fuel duct 30, both of which are hollow so as to convey fuel from the riser 28 to the various branch outlets 3! which supply the jets or nozzles. The riser 28 may bethreadedly connected to the fuel ductby means of an internally threaded hollow boss $2, formed at the outer end of the fuel duct. The inner end of the fuel duct communicates'with the manifold 29, which is mounted thereon. The manifold, is

provided with a series of branch outlet couplers 33 radiating therefrom and equally spaced apart so as to direct equalquantities of fuel to the branch outlets 3i. While it is immaterial how the branch outlet pipes 8! connect with the manifold, it is convenient to furnish a simple threaded connection for the purpose. The threads of the couplers are indicated at M.

The manifold 29 preferably is secured to the bottom plate of the furnace, and for that purpose I the manifold 'may be provided with a series of perforated mounting lugs 35 extending radially outward between the coupling members 33. The

mounting lugs may be bolted, riveted or otherwise secured to the bottom plate 6 of the furnace. The manifold thereby is mounted at the center point of the bottom plate 6, so that all branch outlets 3! may be of equal lengths.

Each branch outlet has an upward extension 36 to which is detachably coupled as at 3"! a nozzle element 38 directed into the furnace interior through an aperture 39 formed in the drum 5. Each nozzle has an orifice 40 for delivering fuel to the comubstion chamber along a line tangential with the lining of the furnace and the outer face of the crucible. As the fuel must pass through the lining material of the furnace, there is preferably provided a jet lining fil of heat resistant material, bored as at 42 to direct the flame in the manner explained. It should be noted that each of the four jets or nozzles disclosed projects its fuel tangentially to the crucible in the space between the crucible and the furnace lining, so that the gases of combustion effectively surround the crucible and travel spirally around it until they reach the exhaust opening IQ of the cover IS. The flame thusly directed does not perform a cutting action tending to Wear away or penetrate any local area of either the crucible or the furnace lining. It has been determined, accordingly, that the life of the crucible and of the lining, have been at least doubled during test operations of the furnace. Moreover the uniform heat distribution effected by the provision of multiple burners working tangentially as explained has resulted in a material reduction of the time required for melting the contents of the crucible, and by thus reducing the working time oxidation and burning of the metal at extremely hot locations, have been materially reduced with the result that a better grade of metal is produced in this furnace than in its predecessors.

In the well known single burner type of furnace, all of the fuel was required to enter the combustion chamber through a single jet, and as the fuel was under high pressure in order to inject the required quantity necessary for establishing a melting temperature, the action at the burner was quite severe, and had a deteriorating effect upon the crucible, the furnace lining and the area surrounding the burner. The effect of this was to ultimately burn away the crucible and the lining at a single locality, and at such locality the metal in the crucible would boil before the metal in other parts of the crucible became fluid. As a result, the quality 'of the metal was relatively poor, due to local burning and oxidation. In the improved device of the present invention, all of the foregoing disadvantages have been obviated. The metal is heated uniformly, and deterioration of the crucible and furnace lining is uniform and slow. Also, the multiple burner arrangement enables the use of a lower fuel pressure at the jets, so that noise and blowing are materially reduced. With these factors under control, the improved furnace operates with a fuel consumption considerably less than is noted in other furnaces of the same general character.

The reference character 33 represents an automatic slag release hole which may be formed in the drum and lining of the furnace, if desired, to permit the escape of any slag or metal that may deposit within the combustion chamber, due to crucible failure or metal spillage. The fuel and air mixer which supplies the combustible mixture of the furnace through the pipe 20, has

not been disclosed as it forms no part of the present invention.

It is to be understood that various modifications and changes in the structural details of the device may be made within the scope of the appended claims, without departing from the spirit of the invention.

What is claimed is:

1. In a device of the class described, the combination of a furnace casing having a side wall and a bottom, and including a combustion chamber, a crucible supported within the combustion chamber in spaced relationship with the furnace side wall, a manifold secured to the furnace bottom and including a series of branch outlets radiating therefrom toward the side wall of the furnace, means supplying fuel to the manifold,

' and a series of fuel nozzles each in communicating relationship with a branch outlet of the manifold for directing fuel to the combustion chamber of the furnace, said nozzles each being supported at an angle such as to direct a series of crucible heating flames on an approximate tangent to the crucible exterior.

2. In a device of the class described, the combination of a furnace casing having a side wall and a bottom, and including a combustion chamber, a crucible supported within the combustion chamber in spaced relationship with the furnace side wall, a manifold fixed relative to the furnace bottom and including a fuel inlet and a distributor head, a series of branch outlets radiating from the distributor head toward the side wall of the furnace, said branch outlets being of equal lengths and extending equal distances from the distributor head, means supplying fuel to the manifold inlet, and a series of fuel nozzles each in communicating relationship with a branch outlet of the manifold for directing fuel to the combustion chamber of the furnace, said nozzles M each being supported at an angle such as to direct a series of crucible heating flames on an approximate tangent to the crucible exterior, and means for bodily tilting the furnace to empty the crucible without disconnection of the fuel supply means aforesaid.

3. In a tilting furnace including a gas fired combustion chamber and abottom plate, a fuel manifold located centrally of the bottom plate, a series of branch outlets of equal length radiating from the fuel manifold and leading to the combustion chamber of the furnace, a fuel duct radiating from the manifold to a location beyond the limits of the furnace bottom and in substantial parallelism therewith, and a fuel inlet on the duct adapted for connection with a fuel supply 4.'In a tilting furnace including a gas fired combustion chamber and a bottom plate, a fuel manifold located centrally of the bottom plate, a series of branch outlets of equal length radiating from the fuel manifold and leading to the combustion chamber of the furnace, a fuel duct radiating from the manifold to a location beyond the limits of the furnace bottom, a fuel inlet port at the outer end of the duct, and fuel supply means including a pipe and a swivel coupling aligned with the tilting axis of the furnace to permit a supply of fuel to the manifold in all tilted positions of the furnace.

5. In a device of the class described, the combination of a furnace drum including a side wall and a bottom, aligned trunnions at opposite sides of the furnace side wall, and a frame including bearings receiving the trunnions for tiltably supporting the furnace drum; a lining for the drum providing a combustion chamber above the drum bottom, a stool in said chamber and a crucible mounted upon the stool in spaced relationship to the lining, a series of fuel nozzles extending through the drum and lining at an angle for clirecting crucible heating gases of combustion tangentially into the space between the crucible and the drum lining, in a common direction such as and means for the equalized distribution of fuel outlet for eachnozzle radiating from the manifold, a fuel duct leading from the manifold to a location beyond the drum bottom, and a fuel supply pipe including a swivel coupling axially aligned with the drum trunnions and connected in fuel transmitting relationship with the outer end of the fuel duct.

CLYDE E. SMALL. 

